Messages

Message types for LLM conversation representation.

Overview

RobotLab uses a structured message system to represent conversations between users, assistants, and tools.

# User input
user_msg = UserMessage.new("Hello", thread_id: "123")

# Assistant response
text_msg = TextMessage.new("Hi there!")

# Tool interaction
tool_call = ToolCallMessage.new(id: "call_1", name: "get_weather", input: { city: "NYC" })
tool_result = ToolResultMessage.new(id: "call_1", result: { temp: 72 })

Message Hierarchy

Message (base)
├── UserMessage      - User input with metadata
├── TextMessage      - Assistant text response
├── ToolMessage      - Tool-related messages
│   ├── ToolCallMessage   - Tool invocation
│   └── ToolResultMessage - Tool result
└── SystemMessage    - System prompts

Common Interface

All messages implement:

message.role       # => Symbol (:user, :assistant, :tool)
message.content    # => String or structured data
message.to_h       # => Hash representation
message.to_json    # => JSON string

Classes

Class	Description
UserMessage	User input with thread and metadata
TextMessage	Assistant text response
ToolCallMessage	Tool invocation request
ToolResultMessage	Tool execution result

Usage in State

Messages are typically accessed through state:

state.messages  # => Array<Message>

# Format for LLM
state.format_history  # => Array<Hash>

See Also

• State
• Message Flow Architecture